A small study of pain reaction, which included 62 older adults with osteoarthritis of the knee, showed that obese people may be more sensitive to pain than those who are not overweight. Before and after completing a 45-minute coping-skills session, study participants—one third of whom were obese—received a mild electrical shock on the left ankle causing tingling and mild pain in the lower leg. The researchers wanted to determine whether coping-skills training, which included progressive muscle-relaxation exercises,would help ease pain. They also were interested in how obese people respond to pain. By measuring the reflex of the lower leg muscles, the researchers determined that the obese participants had a greater physical response to pain than those who were not obese. Study author Charles Emery, professor of psychology at Ohio State University, said: "For subjective indicators of pain, obese people indicated similar levels of pain to nonobese people, but when we looked at objective indicators, we found that the obese group had a lower threshold for pain." Findings from this study were presented at the annual meeting of the American Psychosomatic Society.

Ms. Farley is a freelance medical writer based in Wakefield, RI.